Solve for x:
-(28 x^2)+67 x-40 = 0
The left hand side factors into a product with three terms:
-((4 x-5) (7 x-8)) = 0
Multiply both sides by -1:
(4 x-5) (7 x-8) = 0
Split into two equations:
4 x-5 = 0 or 7 x-8 = 0
Add 5 to both sides:
4 x = 5 or 7 x-8 = 0
Divide both sides by 4:
x = 5/4 or 7 x-8 = 0
Add 8 to both sides:
x = 5/4 or 7 x = 8
Divide both sides by 7:
Answer: | x = 5/4 or x = 8/7
